Development of rational design of a drive equipped with harmonic drive of iron and steel machine

Abstract

The article contains a comparative analysis of well known drives designs with harmonic drive gearing (HDG) intended for application on iron and steel machines. The drives of iron and steel machines equipped with HDG are known to have certain advantages over traditional drives (not equipped with HDG), as their overall dimensions are three times smaller, as compared to conventional ones, they possess smaller labour consumption and lower production costs, lower dynamic loads, it ensuring higher service life and better reliability. Their gear-ratios can reach the value of 500, the performance factor ranging between 0,8-0,9 with high kinematic precision. Still the analyzed drives with HDG have a number of drawbacks, such as: high material capacity, big overall dimensions, a great number of component parts, it leading to reduced service lives and lesser reliability as well as high manufacturing and production costs. This is due to the fact that analyzed designs of drives with HDG were developed without sufficient analysis of technologic capacities of both their components and separate parts, which happen to be bulky and blank parts for their manufacturing are bulky as well and are difficult for mechanical treatment and welding, it drastically increasing production costs for manufacturing chains of HDG. It is known that practically feasible parts are characterized by minimal expenses on their designing, development and manufacturing, as well as repairs and exploitation, so these drawbacks should be eliminated. Thus, the analyzed designs require improvement, by means of implementing a new design of a harmonic drive gearing. The new design will allow to reduce the number of component parts and overall dimensions, production costs, while increasing service life and reliability of the drive. With regard to it the authors have prepared a rational design of a drive, equipped with HDG to applied on iron and steel machines (steel carrying moulds, cast-iron carriers, slag carriages), that drastically improves this appliance